High-Fidelity Transfer of Functional Priors for Wide Bayesian Neural Networks by Learning Activations
- URL: http://arxiv.org/abs/2410.15777v1
- Date: Mon, 21 Oct 2024 08:42:10 GMT
- Title: High-Fidelity Transfer of Functional Priors for Wide Bayesian Neural Networks by Learning Activations
- Authors: Marcin Sendera, Amin Sorkhei, Tomasz Kuśmierczyk,
- Abstract summary: We show how trainable activations can accommodate complex function-space priors on BNNs.
We discuss critical learning challenges, including identifiability, loss construction, and symmetries.
Our empirical findings demonstrate that even BNNs with a single wide hidden layer, can effectively achieve high-fidelity function-space priors.
- Score: 1.0468715529145969
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Function-space priors in Bayesian Neural Networks provide a more intuitive approach to embedding beliefs directly into the model's output, thereby enhancing regularization, uncertainty quantification, and risk-aware decision-making. However, imposing function-space priors on BNNs is challenging. We address this task through optimization techniques that explore how trainable activations can accommodate complex priors and match intricate target function distributions. We discuss critical learning challenges, including identifiability, loss construction, and symmetries that arise in this context. Furthermore, we enable evidence maximization to facilitate model selection by conditioning the functional priors on additional hyperparameters. Our empirical findings demonstrate that even BNNs with a single wide hidden layer, when equipped with these adaptive trainable activations and conditioning strategies, can effectively achieve high-fidelity function-space priors, providing a robust and flexible framework for enhancing Bayesian neural network performance.
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